The present invention relates generally to appliance timers, and more specifically to an appliance timer having an auxiliary switching assembly for increasing switching capacity.
Appliance timers are commonly used in many household appliances, such as dishwashers, clothes washers, and clothes dryers. The appliance timer controls operation of the appliance by actuating and deactuating switch assemblies which start and stop various work functions within the appliance such as a rinse function in the case of a clothes washer. The switch assemblies within the appliance timer are actuated and deactuated as a result of interaction between a number of a cam surfaces defined in a camstack of the appliance timer and a number of assemblies.
The switch assemblies are generally grouped into a number of switch blocks associated with the appliance timer. For example, one common switch block configuration includes eight switch assemblies. Moreover, each of the switch assemblies typically includes an upper circuit blade and a lower circuit blade, with an intermediate circuit blade positioned therebetween. The circuit blades are moved into and out of contact with one another in order to make and break, respectively, a number of circuits. In particular, if the circuit blade has a cam follower molded or otherwise secured thereto, the circuit blade may be moved into and out of contact with other circuit blades via cooperation with one of the cam surfaces defined in the camstack. Alternatively, if the circuit blade is configured without a cam follower, the circuit blade will remain stationary until another circuit blade associated with the switch assembly is moved into or out of contact therewith. One common switch assembly arrangement includes an upper and a lower switch blade each of which is configured without a cam follower. Actuation of the switch assembly occurs as an intermediate circuit blade, which has a cam follower secured thereto, is selectively lifted into contact with the upper circuit blade or dropped into contact with the lower circuit blade.
One way to categorize appliance timers is by the number of switch blocks included in the timer. For example, appliance timers may be categorized as either xe2x80x9csingle blockxe2x80x9d timers or xe2x80x9cdouble blockxe2x80x9d timers. As their respective names suggest, a single block timer includes a single switch block (e.g. a single group of eight switch assemblies in operative contact with the camstack) whereas a double block timer includes two switch blocks (e.g. two groups of switch assemblies each having eight switch assemblies in operative contact with the camstack).
Single block timers advantageously have fewer components relative to double block timers thereby reducing costs associated with the appliance timer. Hence, a number of single block timers have heretofore been designed for use in many household appliances. Such single block timers are used in conjunction with appliances which do not require the additional switching capacity associated with double block timers. For example, it is known that approximately 85% of the clothes washer and dishwasher models available in the appliance market may be operated with a single block timer. Therefore, use of single block timers in such appliances provides the switching capacity necessary to operate the appliance without the additional costs associated with double block timers.
However, the remaining models, often referred to as xe2x80x9chigh-endxe2x80x9d models, generally must be controlled with a more complex timing device such as a double block timer. This is true since such high-end models generally have additional features associated therewith thereby increasing the number of switches required for operation of the appliance. As alluded to above, while use of such double block timers increases the switching capacity associated with the timer, costs associated with the timer are also increased thereby disadvantageously increasing costs associated with the appliance.
What is needed therefore is an appliance timer which has greater switching capacity relative to single block timers which have heretofore been designed. What is further needed is an appliance timer which has greater switching capacity relative to single block timers which have heretofore been designed, but has fewer components relative to double block timers which have heretofore been designed.
In accordance with a first embodiment of the present invention, there is provided a timer for controlling an appliance. The timer includes a camstack having a plurality of cam surfaces defined therein. The timer includes a switch block which cooperates with the plurality of cam surfaces to provide switching operations for the appliance. The timer includes an auxiliary member having a circuit pattern positioned on a side thereof. Rotation of the camstack causes rotation of the auxiliary member. The timer also includes a first switch arm positioned in contact with the side of the auxiliary member. Rotation of the auxiliary member causes the circuit pattern to be advanced into contact with the first switch arm.
In accordance with a second embodiment of the present invention, there is provided a method of controlling an appliance. The appliance includes a timer having (1) a camstack which includes a plurality of cam surfaces defined therein, (2) a switch block having a number of switch assemblies, (3) an auxiliary member having a circuit pattern positioned on a side thereof, and (4) a number of switch arms positioned in contact with the side of the auxiliary member. The method includes the step of rotating the camstack so as to cause the number of switch assemblies to cooperate with the plurality of cam surfaces so as to provide a first number of switching operations for the appliance. The method also includes the step of rotating the auxiliary member so as to cause the number of switch arms to cooperate with the circuit pattern so as to provide a second number of switching operations for the appliance.
In accordance with a third embodiment of the present invention, there is provided a timer for controlling an appliance. The timer includes a housing. The timer also includes a camstack having a plurality of cam surfaces defined therein. The plurality of cam surfaces are positioned within the housing. The timer further includes a switch block which cooperates with the plurality of cam surfaces to provide switching operations for the appliance. Moreover, the timer includes an auxiliary member having a circuit pattern positioned on a side thereof. Rotation of the camstack causes rotation of the auxiliary member. The auxiliary member is positioned outside of the housing. The timer yet further includes a first switch arm positioned in contact with the side of the auxiliary member. Rotation of the auxiliary member causes the circuit pattern to be advanced into contact with the first switch arm.
It is therefore an object of the present invention to provide a new and useful timer for controlling an appliance.
It is a further object of the present invention to provide an improved timer for controlling an appliance.
It is moreover an object of the present invention to provide a new and useful method of controlling an appliance.
It is yet further an object of the present invention to provide an improved method of controlling an appliance.
It is also an object of the present invention to provide an appliance timer that includes an auxiliary switching assembly for increasing the switching capacity associated with the timer.
It is moreover an object of the present invention to provide an appliance timer that utilizes fewer components relative to appliance timers which have heretofore been designed.
It is yet further an object of the present invention to provide an auxiliary switching assembly which may be retrofit to an existing timer thereby increasing the switching capacity associated with the existing timer.
The above and other objects, features, and advantages of the present invention will become apparent from the following description and the attached drawings.